I can only really think of a couple off the top of my head. Cystic fibrosis and Sickle cell anemia are the only ones I know for sure. Albinism may be but I'm not 100% sure.
Many genetic disorders are caused by recessive alleles, but not all of them. Recessive genes do not harm the carrier as long as there is an working version of the allele on the second chromosome...
Many different types of disorders can be found if multiple alleles occur, for example, if your have 3 number 21 chromosomes, then you will have a disorder called "Down Syndrome", so the answer is...
If these genetic disorders were to be caused by homozygous alleles they would selected against and would be removed from the population. The recessive alleles can remain hidden in heterozygotes.